<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>

</body>
<script>
    class father {
        name = "laowang"
        constructor(age, sex) {
            this.age = age
            this.sex = sex
        }
        run = () => {
            console.log("语文");
        }
        speak() {
            console.log("英语");
        }
    }
    let f = new father(18, "男")
    class son extends father {
        constructor(age) {         
            super(age)
          
        }

    }
    let s = new son(2)
    console.log(f);
    console.log(s);
    f.speak()
</script>

</html>